The relationship between demographic and health-related factors on dental service attendance by older Australians.

OBJECTIVE: To determine factors associated with dental attendance by those of 60 years or older in a population-based sample. DESIGN: Cross-sectional national health survey. SETTING: The study used data from the Australian 1995 National Health Survey, which consisted of people interviewed by households. SUBJECTS AND METHODS: A total of 7,544 eligible respondents randomly selected by households from defined statistical areas.Main outcome measures The main outcome investigated in this study was having had a dental visit in the previous 12 months. MAIN RESULTS: Age, income, level of social disadvantage, level of education, uptake of private health insurance, smoking, exercise, self assessment of health and having a health concession card all independently influenced the attendance ratios. In combination, after adjusting for all other factors, factors associated with having visited a dentist for males were age, years of schooling, level of social disadvantage, exercise level index, possession of a health concession card and smoking status. Factors associated with having visited for females were age, education, exercise, smoking status and some levels of the interaction between possession of a health concession card and level of social disadvantage. CONCLUSIONS: The strong influence of age, education, exercise and smoking status indicated a need to target dental services towards those elderly persons in low attendance groups, which mostly represented disadvantaged groups.

Evidence for a novel GTPase priming step in the SRP protein targeting pathway.

Protein targeting by the signal recognition particle (SRP) pathway requires the interaction of two homologous GTPases that reciprocally regulate each other's GTPase activity, the SRP signal peptide- binding subunit (SRP54) and the SRP receptor alpha-subunit (SRalpha). The GTPase domain of both proteins abuts a unique 'N domain' that appears to facilitate external ligand binding. To examine the relationship between the unusual regulation and unique architecture of the SRP pathway GTPases, we mutated an invariant glycine in Escherichia coli SRP54 and SRalpha orthologs ('Ffh' and 'FtsY', respectively) that resides at the N-GTPase domain interface. A G257A mutation in Ffh produced a lethal phenotype. The mutation did not significantly affect Ffh function, but severely reduced interaction with FtsY. Likewise, mutation of FtsY Gly455 produced growth defects and inhibited interaction with Ffh. The data suggest that Ffh and FtsY interact only in a 'primed' conformation which requires interdomain communication. Based on these results, we propose that the distinctive features of the SRP pathway GTPases evolved to ensure that SRP and the SR engage external ligands before interacting with each other.

Physiological basis for conservation of the signal recognition particle targeting pathway in Escherichia coli.

The Escherichia coli signal recognition particle (SRP) is a ribonucleoprotein complex that targets nascent inner membrane proteins (IMPs) to transport sites in the inner membrane (IM). Since SRP depletion only partially inhibits IMP insertion under some growth conditions, however, it is not clear why the particle is absolutely essential for viability. Insights into this question emerged from experiments in which we analyzed the physiological consequences of reducing the intracellular concentration of SRP below the wild-type level. We found that even moderate SRP deficiencies that have little effect on cell growth led to the induction of a heat shock response. Genetic manipulations that suppress the heat shock response were lethal in SRP-deficient cells, indicating that the elevated synthesis of heat shock proteins plays an important role in maintaining cell viability. Although it is conceivable that the heat shock response serves to increase the capacity of cells to target IMPs via chaperone-based mechanisms, SRP-deficient cells did not show an increased dependence on either GroEL or DnaK. By contrast, the heat shock-regulated proteases Lon and ClpQ became essential for viability when SRP levels were reduced. These results suggest that the heat shock response protects SRP-deficient cells by increasing their capacity to degrade mislocalized IMPs. Consistent with this notion, a model IMP that was mislocalized in the cytoplasm as the result of SRP depletion appeared to be more stable in a Deltalon DeltaclpQ strain than in control cells. Taken together, the data provide direct evidence that SRP is essential in E. coli and possibly conserved throughout prokaryotic evolution as well partly because efficient IMP targeting prevents a toxic accumulation of aggregated proteins in the cytoplasm.

Accessibility and spatial distribution of general practice services in an Australian city by levels of social disadvantage.

The accessibility and spatial distribution of health services provided by the main source of primary medical care in Australia--the general practice surgery--was investigated by level of social disadvantage of local catchment areas. All 459 general practice surgeries in Perth, an Australian city of 1.2 million residents, were surveyed with a 94% response. Amount of service provision was measured using weekly doctor-hours, available from consulting rooms during opening hours, and associated nurse-hours of service. Access factors were defined as the distance to the nearest surgery, provision of Sunday and evening services, ease of making a same day appointment, bulk-billing, and whether the surgery offered a choice of gender of doctor. There were relatively more surgeries in disadvantaged areas and doctor-hours of service provision were also greater (41.0 h/1,000 most disadvantaged vs. 37.9 h/1000 least disadvantaged). Bulk-billing care, at no direct cost to the patient, was more likely to be provided in most disadvantaged areas compared with least disadvantaged areas (61 vs. 38%). However, populations living in the most disadvantaged areas were less likely to be able to see the local GP at short notice (91 vs. 95%), to have access to a local female GP (56 vs. 62%) or a local service in the evenings (42 vs. 51%). While the overall picture of accessibility was favourable, there was considerable variation in the type of services provided to different socioeconomic groups. Health care planners should investigate the reasons for these differences and advise Government to ensure that access factors affecting publicly funded services are equitably distributed.

Effect of distance and social disadvantage on the response to invitations to attend mammography screening.

STUDY OBJECTIVES: To investigate whether public response to an invitation to attend mammography screening can be increased by strategic relocation of the clinics. METHODS: Women invited to attend mammography screening were classified by attendance, socioeconomic status, and distance from their screening clinic. A geographic information system was used to investigate whether the response could be increased by relocating clinics to facilitate access. SETTING: The metropolitan city of Perth in Western Australia with six fixed site, publicly funded, mammography screening clinics. MAIN RESULTS: Women from disadvantaged areas, not screened previously by the mammography screening programme, had a higher response to an invitation to attend screening if they lived within 3 km of their closest clinics (12%) than if they lived further away (8%). Theoretically, the response of the target population could be increased if the existing clinics were replaced by six new clinics located closer to disadvantaged areas. CONCLUSIONS: Public health planners should be aware of the use of geographic information systems to model optimum locations of health care facilities, and be willing to assess the potential target population response to those locations.

Differential effects on socioeconomic groups of modelling the location of mammography screening clinics using Geographic Information Systems.

OBJECTIVE: To evaluate spatial access to mammography clinics and to investigate whether relocating clinics can improve global access. To determine whether any change in access is distributed equitably between different social groups. METHODS: The study was undertaken in Perth, Western Australia in 1996. It was an analysis of travel distances to mammography clinics, comparing distances to the pattern of existing clinics and modelled relocated clinics. The study population was the 151,162 women aged 40-64 years resident in Perth in 1991. RESULTS: Overall travel distances to the existing clinics was reduced by 14% when a GIS system was used to relocate them so as to minimise the travel distance for all women. The travel distance of the most disadvantaged groups fell by 2% and by 24% for the least disadvantaged group. CONCLUSIONS: GIS modelling can be used to advantage to evaluate potential locations for screening clinics that improve the access for the target population, however global analysis should be supplemented by analysis of special groups to ensure that no group is disadvantaged by the proposal. IMPLICATIONS: If new technology is not used to evaluate the placement of health services, population travel distances may be greater than necessary, with possible impacts on attendance rates.

Nutritional counselling in general practice: a cost effective analysis.

STUDY OBJECTIVE: To study the clinical and cost outcomes of providing nutritional counselling to patients with one or more of the following conditions: overweight, hypertension and type 2 diabetes. DESIGN: The study was designed as a random controlled trial. Consecutive patients were screened opportunistically for one or more of the above conditions and randomly allocated to one of two intervention groups (doctor/dietitian or dietitian) or a control group. Both intervention groups received six counselling sessions over 12 months from a dietitian. However, in the doctor/dietitian group it was the doctor and not the dietitian who invited the patient to join the study and the same doctor also reviewed progress at two of the six counselling sessions. SETTING: The study was conducted in a university group general practice set in a lower socioeconomic outer suburb of Perth, Western Australia. PATIENTS: Of the 273 patients randomly allocated to a study group, 198 were women. Age ranged from 25 to 65 years. Seventy eight per cent of patients resided in the lower two socioecnomic quartiles, 56 per cent described their occupation as home duties and 78 per cent were partnered. RESULTS: Both intervention groups reduced weight and blood pressure compared with the control group. Patients in the doctor/dietitian group were more likely to complete the 12 month programme than those in the dietitian group. Patients in the doctor/dietitian group lost an average of 6.7 kg at a cost of $A9.76 per kilogram, while the dietitian group lost 5.6 kg at a cost of $A7.30 per kilogram. CONCLUSION: General practitioners, in conjunction with a dietitian, can produce significant weight and blood pressure improvement by health promotion methods.

A comparison of measures of access to child health clinics and the implications for modelling the location of new clinics.

OBJECTIVE: To determine whether measurement of access to existing child health clinics, and modelled location of new clinics, was affected by the spatial definitions of the target population. METHOD: Populations requiring childhood screening services were defined as located at individual households, and at geographic and population-weighted centroids of small and large areas. Straight-line and network distances were measured and compared from these origins to varying numbers of existing clinics. The same origins were used to model sets of locations for new clinics, and access levels were again compared. RESULTS: Travel distances for 82,499 annual baby-visits to 140 existing clinics were between 136,000 km and 84,000 km, depending on origin definition. An analysis based on small area centroid data was as accurate as one based on household data. Planning solutions for new clinics located on the basis of few large areas, with populations centred at spatially defined centroids, resulted in poorer access for the population (231,000 km of travel) than one based on many small areas with populations centred at population weighted centroids (194,000 km of travel). IMPLICATIONS: Public access to health facilities will be improved if decisions about their locations are aided by the application of spatial analysis techniques based on small area definitions.

The effect of spatial definition on the allocation of clients to screening clinics.

We compared four strategies for inviting 91,456 women aged 50-69 years to one of six clinics for mammography screening and 40,142 men aged 60-79 years to one of 10 clinics for abdominal aortic aneurysm (AAA) screening. The strategies were invitation to the clinic nearest to the client and invitation to the clinic nearest to the client's area of residence defined by census small area, postcode and local government area. For each strategy we calculated the expected demand at each clinic and the travel distances for clients. We found that when women were allocated to mammography clinics on the basis of the local government area instead of their individual address, expected demand at one clinic increased by 60%, and 19% of clients were invited to attend a more remote clinic, entailing 99,000 km of additional travel. Similar results were obtained for men allocated to AAA clinics by their postcode of residence instead of their individual address: 55% difference in expected demand, 13% to a more remote clinic and 60,000 km of extra travel. Allocation on the basis of small areas did not show such great differences, except for travel distance, which was about 5% higher for each clinic type. We recommend that allocation of clients to screening clinics be made according to residential address, that assessment of the location of clinics be based on distances between residences and nearest clinic, but that planning new locations for clinics be aided with spatial analysis tools using small area demographic and social data.

Estimating the cost of an interview survey using geographic information system software.

Estimating the cost of interview surveys is difficult but important. A geographic information system (GIS) was used to determine the shortest time route to survey 533 medical facility locations in Perth. The results provided time and cost estimates for undertaking the survey and the interviewer agreed to a contract for the job on the basis of these estimates.

Cervical cancer: an inpatient screening service.

This paper describes the implementation and patient and staff acceptance of a pilot cervical cancer screening service for women aged 20 to 69 years who were inpatients in a 700 bed teaching hospital in Perth, Western Australia. Eligible women were identified daily by using the hospital admission lists, reviewing medical records and, where necessary, consulting with staff. Patients' and staff's acceptance of the service was evaluated by interviews and self-administered questionnaires. Thirty-five percent of the women whose records could be examined needed a Pap smear and 72% of these women had a smear. Fifty-five percent of women screened were aged from 50 to 69 years and 29% had not previously had a Pap smear. Patients and staff were very satisfied with the service and its continuation was strongly supported by the hospital's administrative, nursing and medical personnel. Based on 4000 admissions of women in the 20 to 69 age group and 684 smears per year, the projected annual cost of the service is $46,000. The service proved to be an effective strategy for reaching underscreened women and its success demonstrates the important role that nurses can play in reducing the morbidity and mortality caused by cervical cancer.

Cost-effectiveness of interventions to promote cervical screening in general practice.

A cost-effectiveness study of three different interventions to promote the uptake of screening for cervical cancer in general practice was carried out in Perth in 1991. Women eligible for a Pap smear were randomly allocated to one of four groups: one receiving letters with specific appointments to attend a screening clinic staffed by female doctors, one receiving letters informing them of the availability of the clinic and suggesting they make an appointment, one whose files were tagged to remind a doctor to offer a smear during a consultation, and a comparison control group that received opportunistic screening only. Variable and fixed costs for each group were itemised and summarised to give an average cost per smear taken. The cost and effectiveness of each intervention were then compared with those of the control group. Sensitivity analysis was performed on the major component of the costs, the doctor's time. Opportunistic screening cost $14.60 per smear and attained 16 per cent recruitment. Tagging files was the cheapest intervention ($14.75 per smear) although it was the least effective in recruiting women (20 per cent). This result held true for different scenarios of doctor's time allocated. Intervention by invitation letter with no appointment cost $45.35 per smear and attained 26 per cent recruitment, and intervention with a specific appointment cost $48.21 per smear and attained 30 per cent recruitment. Compared with the control group, the incremental cost-effectiveness for the tagged group was $15.40, for the letter-without-appointment group $97.75 and for the letter-with-appointment group $86.50.

Cervical cancer screening for hospital inpatients: report of an intervention study.

A pilot study of a cervical cancer screening service was carried out at a major teaching hospital in Perth. The service, for women inpatients aged 20 to 69 years, was staffed by a women's health nurse. The effect of providing the service (service) was compared with giving a leaflet on Pap smears to eligible women (education) and with no intervention (control). Of 517 women in the service group, 184 (36 per cent) needed a Pap smear and were well enough to be offered screening; only 29 of 184 (16 per cent) refused and 132 of 184 (72 per cent) were screened. Of those screened, 29 per cent had never had a Pap smear. Information on women in the education and control groups was obtained by mailed questionnaire. Of the eligible women in the service group, 72 per cent accepted screening in hospital, but only 24 per cent of eligible women in the education group and 20 per cent in the control group reported having a Pap smear in the four months since leaving hospital. The service group showed a very large effect relative to the control group (odds ratio (OR) 17.71, 95 per cent confidence interval (CI) 10.05 to 31.22), but there was no significant difference between the education and control groups. Other significant variables in the logistic regression model were age, marital status, and sex of the woman's general practitioner. The effect of offering the service was greater for women over 50 (OR 51.51, CI 19.01 to 139.60) A hospital-based cervical screening service provides an important opportunity for screening women who are not being reached by other services.

Cervical screening in general practice.

This study examined the effect of three interventions for encouraging women to have a Pap smear in a general practice: tagging the medical record to remind the doctor to offer a Pap smear, sending an invitation to make an appointment for a Pap smear, and sending an invitation with an appointment to attend for a Pap smear at a special screening clinic staffed by women. The study took place in a university general practice at Lockridge, near Perth. A computerised practice age-sex register provided 2139 women in the age range 36 to 69 inclusive. Of these, 757 were eligible for inclusion in the study and were allocated randomly to one of three intervention groups or a control group. In total, 177 women had a Pap smear during the study. Significantly more Pap smears were taken for the appointment-letter and letter-only groups than the control group (odds ratio (OR) 2.13, 95% confidence interval (CI) 1.34 to 3.57, and OR 1.67, CI 1.01 to 2.77 respectively), but there was no significant difference between the tagged-notes and the control groups. Women who attended the screening clinic rated the experience positively. Attendance, however, was inadequate for the clinic's viability in a private practice.

Misclassification of social disadvantage based on geographical areas: comparison of postcode and collector's district analyses.

BACKGROUND: Analysis of socioeconomic status (SES), defined on the basis of geographical area, will always be subject to misclassification of individuals. We studied the relationship between SES and selected health-related measures when SES was defined firstly on the basis of postcode and secondly on the basis of the smaller spatial area of collector's district (CD). METHOD: A Census population of 1.4 million was used to investigate the misclassification of individuals to SES group using postcode as opposed to CD. A field survey of 1000 respondents and a mortality register of 1756 deaths were used to compare the relationship between SES and certain outcome variables, when SES group was assigned using postcode and CD. Misclassification probability matrices were used to try to adjust the postcode-based results to approximate CD-based results. RESULTS: The Census data showed that nearly 50% of residents were misclassified into SES groups by the postcode-based system compared with a CD-based system. In comparing the most socially disadvantaged group with the least disadvantaged group, the postcode analysis underestimated the absolute effects of SES by 58% for the increased prevalence of smoking, by 19% for the reduced prevalence of participation in junior sporting clubs and by 13% for the increased mortality rate at ages 0-64 years. Adjustment of postcode-based results using misclassification matrices proved fruitless due to differential misclassification and technical difficulties. CONCLUSIONS: Misclassification of individuals to SES groups on the basis of postcode has caused an underestimation of the true relationship between SES and health-related measures. A reduction of this misclassification by using smaller spatial areas, such as CD or census enumeration districts, will provide improved validity in estimating the true relationship.

Rotational osteotomies of the leg: tibia alone versus both tibia and fibula.

From a chart review of 45 consecutive cases (mean age 8.9 years) of patients who had rotational osteotomies of the tibia alone (group 1, 27 cases) or of both the tibia and fibula (group 2, 18 cases) for torsional deformities of the leg, we compared the length of surgery and postoperative complications. We also describe the surgical technique for tibial osteotomy alone. The most common complication, posterior and varus/valgus angulation at the osteotomy site, was significantly higher in group 2 than in group 1 (p < 0.05). The mean operative time was 21% faster for tibial osteotomy alone. One case of chronic lateral compartment syndrome occurred in group 2. When indicated, tibial osteotomy alone is a simple, safe, fast, and stable surgical procedure for correcting excessive tibial torsion.

Short arm plaster cast for distal pediatric forearm fractures.

Ten years' clinical experience with below-elbow plaster cast treatment of distal one third pediatric forearm fractures was subjected to an independent retrospective radiographic review. In the study population of 761 fractures, no significant displacement occurred while the forearm remained in plaster. The average angulation change was 4.5 degrees (SD +/- 2.2 degrees). In each angulation change > 5 degrees, poor cast molding was evident, as reflected by a high "cast index" (p < 0.01). Although this technique is technically demanding, excellent results are obtained in all distal pediatric forearm fractures if proper cast molding is used.

Cubitus varus: significant factors.

For better understanding of the etiology of "post-supracondylar fracture cubitus varus," an in vitro anatomic experiment was performed. Elbow models were precisely photographed in 256 combinations of 10 degrees increments of varus angulation, posterior angulation, internal rotation, and/or flexion contracture. Varus angulation was the most important single factor contributing to deformity. Addition of flexion contracture or posterior angulation to a given varus angulation decreased apparent deformity, whereas addition of internal rotation worsened the deformity. Control of varus angulation in the clinical setting, by whatever method, should minimize post-supracondylar fracture cubitus varus.

A study of the characteristics and needs of people transferred from acute hospitals to nursing homes.

OBJECTIVES: To describe the categories of people being approved for admission to nursing homes; to consider whether any alternatives would have been more appropriate; and to outline the care needed for each category. PARTICIPANTS AND SETTING: Patients in acute-care facilities in metropolitan Perth for whom a request had been made for nursing home admission. DESIGN: Patients were interviewed (by R B L and M D) and records in the acute hospital were examined. A second interview of those patients still available was conducted after their transfer to the nursing home. RESULTS: Nursing care was considered necessary for 123 of the 201 people seen in the acute hospitals; domestic care in a standard hostel for 24 people; care in a special dementia unit (SDU) hostel for 26 people; and care in a psychiatric institution for 16 people. Twelve others had various specific needs. Several different categories were identified in the group needing nursing care. CONCLUSIONS: Applicants for nursing home admission do not form a homogeneous group; there are several categories with different needs. SDU hostels should be added to the available facilities. In addition to undertaking the assessment of nursing home applicants, personnel from geriatric services should be encouraged to become involved in their continuing care.